This prospective study was to describe the incidence and characteristics of physical activity-related injuries (PARI) among college students in southern China. Online questionnaires and telephone interviews were combined to investigate the physical activity (PA) participation and PARI occurrences every two weeks. Totally, 84 college students (men: 49; women: 35) with a mean age of 19.4 years completed the entire 1-year follow-up. Overall, 14250.3 PA exposure hours were collected and 36 PARI episodes were reported by 26 students, with an injury incidence density of 2.53 injuries per 1000 PA exposure hours and an injury risk of 0.43 injuries/student/year. July to September accounted for a highest proportion of injuries and half of the injuries happened in the evening. The majority of injuries occurred outdoors, happened in non-contact activities, were acute and involved the lower limbs, with sprains and strains being the primary injury types. Of all injuries, 80.6% resulted in PA withdrawal immediately and 58.3% led to absence from the next planned PA. No significant difference was found between men and women. This study reveals the problem of PARI among college students, which provides the direction for the prevention of PARI in this population.